Reduce use of LocalDefId <-> HirId maps

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -409,8 +409,9 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     let generics = tcx.generics_of(self.mir_def_id());
                     let param = generics.type_param(&param_ty, tcx);
                     if let Some(generics) = tcx
-                        .hir()
-                        .get_generics(tcx.typeck_root_def_id(self.mir_def_id().to_def_id()))
+                        .typeck_root_def_id(self.mir_def_id().to_def_id())
+                        .as_local()
+                        .and_then(|def_id| tcx.hir().get_generics(def_id))
                     {
                         suggest_constraining_type_param(
                             tcx,

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -628,42 +628,39 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         };
         (
             true,
-            td.as_local().and_then(|tld| {
-                let h = hir_map.local_def_id_to_hir_id(tld);
-                match hir_map.find(h) {
-                    Some(Node::Item(hir::Item {
-                        kind: hir::ItemKind::Trait(_, _, _, _, items),
-                        ..
-                    })) => {
-                        let mut f_in_trait_opt = None;
-                        for hir::TraitItemRef { id: fi, kind: k, .. } in *items {
-                            let hi = fi.hir_id();
-                            if !matches!(k, hir::AssocItemKind::Fn { .. }) {
-                                continue;
-                            }
-                            if hir_map.name(hi) != hir_map.name(my_hir) {
-                                continue;
-                            }
-                            f_in_trait_opt = Some(hi);
-                            break;
+            td.as_local().and_then(|tld| match hir_map.find_by_def_id(tld) {
+                Some(Node::Item(hir::Item {
+                    kind: hir::ItemKind::Trait(_, _, _, _, items),
+                    ..
+                })) => {
+                    let mut f_in_trait_opt = None;
+                    for hir::TraitItemRef { id: fi, kind: k, .. } in *items {
+                        let hi = fi.hir_id();
+                        if !matches!(k, hir::AssocItemKind::Fn { .. }) {
+                            continue;
                         }
-                        f_in_trait_opt.and_then(|f_in_trait| match hir_map.find(f_in_trait) {
-                            Some(Node::TraitItem(hir::TraitItem {
-                                kind:
-                                    hir::TraitItemKind::Fn(
-                                        hir::FnSig { decl: hir::FnDecl { inputs, .. }, .. },
-                                        _,
-                                    ),
-                                ..
-                            })) => {
-                                let hir::Ty { span, .. } = inputs[local.index() - 1];
-                                Some(span)
-                            }
-                            _ => None,
-                        })
+                        if hir_map.name(hi) != hir_map.name(my_hir) {
+                            continue;
+                        }
+                        f_in_trait_opt = Some(hi);
+                        break;
                     }
-                    _ => None,
+                    f_in_trait_opt.and_then(|f_in_trait| match hir_map.find(f_in_trait) {
+                        Some(Node::TraitItem(hir::TraitItem {
+                            kind:
+                                hir::TraitItemKind::Fn(
+                                    hir::FnSig { decl: hir::FnDecl { inputs, .. }, .. },
+                                    _,
+                                ),
+                            ..
+                        })) => {
+                            let hir::Ty { span, .. } = inputs[local.index() - 1];
+                            Some(span)
+                        }
+                        _ => None,
+                    })
                 }
+                _ => None,
             }),
         )
     }
@@ -896,7 +893,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         if look_at_return && hir.get_return_block(closure_id).is_some() {
             // ...otherwise we are probably in the tail expression of the function, point at the
             // return type.
-            match hir.get(hir.get_parent_item(fn_call_id)) {
+            match hir.get_by_def_id(hir.get_parent_item(fn_call_id)) {
                 hir::Node::Item(hir::Item { ident, kind: hir::ItemKind::Fn(sig, ..), .. })
                 | hir::Node::TraitItem(hir::TraitItem {
                     ident,
@@ -1075,8 +1072,7 @@ fn get_mut_span_in_struct_field<'tcx>(
         if let ty::Adt(def, _) = ty.kind() {
             let field = def.all_fields().nth(field.index())?;
             // Use the HIR types to construct the diagnostic message.
-            let hir_id = tcx.hir().local_def_id_to_hir_id(field.did.as_local()?);
-            let node = tcx.hir().find(hir_id)?;
+            let node = tcx.hir().find_by_def_id(field.did.as_local()?)?;
             // Now we're dealing with the actual struct that we're going to suggest a change to,
             // we can expect a field that is an immutable reference to a type.
             if let hir::Node::Field(field) = node {

compiler/rustc_borrowck/src/diagnostics/region_name.rs

@@ -704,7 +704,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                         hir::AsyncGeneratorKind::Block => " of async block",
                         hir::AsyncGeneratorKind::Closure => " of async closure",
                         hir::AsyncGeneratorKind::Fn => {
-                            let parent_item = hir.get(hir.get_parent_item(mir_hir_id));
+                            let parent_item = hir.get_by_def_id(hir.get_parent_item(mir_hir_id));
                             let output = &parent_item
                                 .fn_decl()
                                 .expect("generator lowered from async fn should be in fn")

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -76,7 +76,7 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, cnum: CrateNum) -> DefIdMap<
             //
             // As a result, if this id is an FFI item (foreign item) then we only
             // let it through if it's included statically.
-            match tcx.hir().get(tcx.hir().local_def_id_to_hir_id(def_id)) {
+            match tcx.hir().get_by_def_id(def_id) {
                 Node::ForeignItem(..) => {
                     tcx.is_statically_included_foreign_item(def_id).then_some(def_id)
                 }

compiler/rustc_const_eval/src/const_eval/fn_queries.rs

@@ -1,5 +1,5 @@
 use rustc_hir as hir;
-use rustc_hir::def_id::DefId;
+use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::symbol::Symbol;
@@ -15,7 +15,8 @@ pub fn is_unstable_const_fn(tcx: TyCtxt<'_>, def_id: DefId) -> Option<Symbol> {
     }
 }
 
-pub fn is_parent_const_impl_raw(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool {
+pub fn is_parent_const_impl_raw(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
+    let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
     let parent_id = tcx.hir().get_parent_node(hir_id);
     matches!(
         tcx.hir().get(parent_id),
@@ -29,15 +30,15 @@ pub fn is_parent_const_impl_raw(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool {
 /// Checks whether the function has a `const` modifier or, in case it is an intrinsic, whether
 /// said intrinsic has a `rustc_const_{un,}stable` attribute.
 fn is_const_fn_raw(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
-    let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
-
-    let node = tcx.hir().get(hir_id);
+    let def_id = def_id.expect_local();
+    let node = tcx.hir().get_by_def_id(def_id);
 
     if let hir::Node::ForeignItem(hir::ForeignItem { kind: hir::ForeignItemKind::Fn(..), .. }) =
         node
     {
         // Intrinsics use `rustc_const_{un,}stable` attributes to indicate constness. All other
         // foreign items cannot be evaluated at compile-time.
+        let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
         if let Abi::RustIntrinsic | Abi::PlatformIntrinsic = tcx.hir().get_foreign_abi(hir_id) {
             tcx.lookup_const_stability(def_id).is_some()
         } else {
@@ -50,7 +51,7 @@ fn is_const_fn_raw(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
 
         // If the function itself is not annotated with `const`, it may still be a `const fn`
         // if it resides in a const trait impl.
-        is_parent_const_impl_raw(tcx, hir_id)
+        is_parent_const_impl_raw(tcx, def_id)
     } else {
         matches!(node, hir::Node::Ctor(_))
     }

compiler/rustc_const_eval/src/transform/check_consts/check.rs

@@ -221,8 +221,7 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
             // Prevent const trait methods from being annotated as `stable`.
             // FIXME: Do this as part of stability checking.
             if self.is_const_stable_const_fn() {
-                let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
-                if crate::const_eval::is_parent_const_impl_raw(tcx, hir_id) {
+                if crate::const_eval::is_parent_const_impl_raw(tcx, def_id) {
                     self.ccx
                         .tcx
                         .sess

compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs

@@ -210,8 +210,7 @@ impl Qualif for CustomEq {
         // because that component may be part of an enum variant (e.g.,
         // `Option::<NonStructuralMatchTy>::Some`), in which case some values of this type may be
         // structural-match (`Option::None`).
-        let id = cx.tcx.hir().local_def_id_to_hir_id(cx.def_id());
-        traits::search_for_structural_match_violation(id, cx.body.span, cx.tcx, ty).is_some()
+        traits::search_for_structural_match_violation(cx.body.span, cx.tcx, ty).is_some()
     }
 
     fn in_adt_inherently<'tcx>(

compiler/rustc_hir/src/hir_id.rs

@@ -19,11 +19,13 @@ pub struct HirId {
 }
 
 impl HirId {
+    #[inline]
     pub fn expect_owner(self) -> LocalDefId {
         assert_eq!(self.local_id.index(), 0);
         self.owner
     }
 
+    #[inline]
     pub fn as_owner(self) -> Option<LocalDefId> {
         if self.local_id.index() == 0 { Some(self.owner) } else { None }
     }

compiler/rustc_incremental/src/persist/dirty_clean.rs

@@ -223,8 +223,7 @@ impl<'tcx> DirtyCleanVisitor<'tcx> {
     /// Return all DepNode labels that should be asserted for this item.
     /// index=0 is the "name" used for error messages
     fn auto_labels(&mut self, item_id: LocalDefId, attr: &Attribute) -> (&'static str, Labels) {
-        let hir_id = self.tcx.hir().local_def_id_to_hir_id(item_id);
-        let node = self.tcx.hir().get(hir_id);
+        let node = self.tcx.hir().get_by_def_id(item_id);
         let (name, labels) = match node {
             HirNode::Item(item) => {
                 match item.kind {

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -151,11 +151,10 @@ fn msg_span_from_early_bound_and_free_regions<'tcx>(
 ) -> (String, Span) {
     let sm = tcx.sess.source_map();
 
-    let scope = region.free_region_binding_scope(tcx);
-    let node = tcx.hir().local_def_id_to_hir_id(scope.expect_local());
+    let scope = region.free_region_binding_scope(tcx).expect_local();
     match *region {
         ty::ReEarlyBound(ref br) => {
-            let mut sp = sm.guess_head_span(tcx.hir().span(node));
+            let mut sp = sm.guess_head_span(tcx.def_span(scope));
             if let Some(param) =
                 tcx.hir().get_generics(scope).and_then(|generics| generics.get_named(br.name))
             {
@@ -166,7 +165,7 @@ fn msg_span_from_early_bound_and_free_regions<'tcx>(
         ty::ReFree(ty::FreeRegion {
             bound_region: ty::BoundRegionKind::BrNamed(_, name), ..
         }) => {
-            let mut sp = sm.guess_head_span(tcx.hir().span(node));
+            let mut sp = sm.guess_head_span(tcx.def_span(scope));
             if let Some(param) =
                 tcx.hir().get_generics(scope).and_then(|generics| generics.get_named(name))
             {
@@ -181,13 +180,13 @@ fn msg_span_from_early_bound_and_free_regions<'tcx>(
                 } else {
                     (
                         format!("the anonymous lifetime #{} defined here", idx + 1),
-                        tcx.hir().span(node),
+                        tcx.def_span(scope),
                     )
                 }
             }
             _ => (
                 format!("the lifetime `{}` as defined here", region),
-                sm.guess_head_span(tcx.hir().span(node)),
+                sm.guess_head_span(tcx.def_span(scope)),
             ),
         },
         _ => bug!(),
@@ -1759,8 +1758,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         if let Some(ValuePairs::PolyTraitRefs(exp_found)) = values {
             if let ty::Closure(def_id, _) = exp_found.expected.skip_binder().self_ty().kind() {
                 if let Some(def_id) = def_id.as_local() {
-                    let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id);
-                    let span = self.tcx.hir().span(hir_id);
+                    let span = self.tcx.def_span(def_id);
                     diag.span_note(span, "this closure does not fulfill the lifetime requirements");
                 }
             }
@@ -2212,9 +2210,9 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                     if let Some(Node::Item(Item {
                         kind: ItemKind::Trait(..) | ItemKind::Impl { .. },
                         ..
-                    })) = hir.find(parent_id)
+                    })) = hir.find_by_def_id(parent_id)
                     {
-                        Some(self.tcx.generics_of(hir.local_def_id(parent_id).to_def_id()))
+                        Some(self.tcx.generics_of(parent_id))
                     } else {
                         None
                     },
@@ -2245,7 +2243,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                         if let Node::GenericParam(param) = hir.get(id) {
                             has_bounds = !param.bounds.is_empty();
                         }
-                        let sp = hir.span(id);
+                        let sp = self.tcx.def_span(def_id);
                         // `sp` only covers `T`, change it so that it covers
                         // `T:` when appropriate
                         let is_impl_trait = bound_kind.to_string().starts_with("impl ");
@@ -2291,12 +2289,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             .as_ref()
             .and_then(|(_, g, _)| g.params.first())
             .and_then(|param| param.def_id.as_local())
-            .map(|def_id| {
-                (
-                    hir.span(hir.local_def_id_to_hir_id(def_id)).shrink_to_lo(),
-                    format!("{}, ", new_lt),
-                )
-            });
+            .map(|def_id| (self.tcx.def_span(def_id).shrink_to_lo(), format!("{}, ", new_lt)));
 
         let labeled_user_string = match bound_kind {
             GenericKind::Param(ref p) => format!("the parameter type `{}`", p),

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/static_impl_trait.rs

@@ -187,6 +187,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
             | ObligationCauseCode::BlockTailExpression(hir_id) = cause.code()
             {
                 let parent_id = tcx.hir().get_parent_item(*hir_id);
+                let parent_id = tcx.hir().local_def_id_to_hir_id(parent_id);
                 if let Some(fn_decl) = tcx.hir().fn_decl_by_hir_id(parent_id) {
                     let mut span: MultiSpan = fn_decl.output.span().into();
                     let mut add_label = true;
@@ -425,7 +426,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
         let tcx = self.tcx();
         match tcx.hir().get_if_local(def_id) {
             Some(Node::ImplItem(impl_item)) => {
-                match tcx.hir().find(tcx.hir().get_parent_item(impl_item.hir_id())) {
+                match tcx.hir().find_by_def_id(tcx.hir().get_parent_item(impl_item.hir_id())) {
                     Some(Node::Item(Item {
                         kind: ItemKind::Impl(hir::Impl { self_ty, .. }),
                         ..
@@ -434,13 +435,13 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
                 }
             }
             Some(Node::TraitItem(trait_item)) => {
-                let parent_id = tcx.hir().get_parent_item(trait_item.hir_id());
-                match tcx.hir().find(parent_id) {
+                let trait_did = tcx.hir().get_parent_item(trait_item.hir_id());
+                match tcx.hir().find_by_def_id(trait_did) {
                     Some(Node::Item(Item { kind: ItemKind::Trait(..), .. })) => {
                         // The method being called is defined in the `trait`, but the `'static`
                         // obligation comes from the `impl`. Find that `impl` so that we can point
                         // at it in the suggestion.
-                        let trait_did = tcx.hir().local_def_id(parent_id).to_def_id();
+                        let trait_did = trait_did.to_def_id();
                         match tcx
                             .hir()
                             .trait_impls(trait_did)

compiler/rustc_infer/src/infer/opaque_types.rs

@@ -635,7 +635,7 @@ fn may_define_opaque_type(tcx: TyCtxt<'_>, def_id: LocalDefId, opaque_hir_id: hi
     let scope = tcx.hir().get_defining_scope(opaque_hir_id);
     // We walk up the node tree until we hit the root or the scope of the opaque type.
     while hir_id != scope && hir_id != hir::CRATE_HIR_ID {
-        hir_id = tcx.hir().get_parent_item(hir_id);
+        hir_id = tcx.hir().local_def_id_to_hir_id(tcx.hir().get_parent_item(hir_id));
     }
     // Syntactically, we are allowed to define the concrete type if:
     let res = hir_id == scope;

compiler/rustc_lint/src/builtin.rs

@@ -610,8 +610,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
                 // reported for missing docs.
                 let real_trait = trait_ref.path.res.def_id();
                 let Some(def_id) = real_trait.as_local() else { return };
-                let hir_id = cx.tcx.hir().local_def_id_to_hir_id(def_id);
-                let Some(Node::Item(item)) = cx.tcx.hir().find(hir_id) else { return };
+                let Some(Node::Item(item)) = cx.tcx.hir().find_by_def_id(def_id) else { return };
                 if let hir::VisibilityKind::Inherited = item.vis.node {
                     for impl_item_ref in items {
                         self.private_traits.insert(impl_item_ref.id.hir_id());
@@ -656,7 +655,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
 
         // If the method is an impl for an item with docs_hidden, don't doc.
         if method_context(cx, impl_item.hir_id()) == MethodLateContext::PlainImpl {
-            let parent = cx.tcx.hir().get_parent_did(impl_item.hir_id());
+            let parent = cx.tcx.hir().get_parent_item(impl_item.hir_id());
             let impl_ty = cx.tcx.type_of(parent);
             let outerdef = match impl_ty.kind() {
                 ty::Adt(def, _) => Some(def.did),
@@ -1212,7 +1211,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidNoMangleItems {
                             check_no_mangle_on_generic_fn(
                                 no_mangle_attr,
                                 Some(generics),
-                                cx.tcx.hir().get_generics(it.id.def_id.to_def_id()).unwrap(),
+                                cx.tcx.hir().get_generics(it.id.def_id).unwrap(),
                                 it.span,
                             );
                         }